This invention relates to file folders serially connected to constitute a web of indeterminate length. The web is formed of two face-to-face oriented sheets and is, at the supply end, rolled up or folded in a zigzag manner. Expediently, the web has a hole series extending lengthwise at the web edges for cooperation with paper feed sprockets in typewriters, or the like. This hole series will also be designated hereinafter as "apertured margin".
File folders of the above type serve for accommodating papers and can be provided with inscription directly by typewriters with or without carbon-copying.
Envelopes are known wherein two paper webs are glued to one another along peripheral edges in such a manner that an insert sleeve is obtained. These paper webs are provided bilaterally with an apertured margin; the flaps for closing the sleeves are stamped from the paper web in accordance with the desired shape. The envelopes of this type serve principally for the dispatch of papers; they are less adapted for use as storage means in file systems because they are closed at least along three sides and therefore cannot be folded open.
It is further known to glue openable file folders with folded-in lateral flaps on carrier webs of indeterminate length. In such a structure, however, it is required that the file folders be made in a separate stamping and folding process and they have to be glued in a further work process on the carrier webs which also have to be separately manufactured. In such a structure, in the zone of the folded-in lateral flaps, a total of four material layers are superimposed. This results in a disadvantageous overall thickness of the web, particularly when it is used in connection with carbon copying. Particularly in certain rapid printers associated with electronic data processing, (hereinafter referred to as "rapid EDP-printers") it is impossible to type on envelope structures of this kind.